What are the management recommendations for subsequent pregnancies following wedge resection for cornual (cornual ectopic pregnancy)/interstitial ectopic pregnancy to minimize the risk of uterine rupture?

Management of Subsequent Pregnancies Following Wedge Resection for Cornual/Interstitial Ectopic Pregnancy

Subsequent pregnancies after cornual wedge resection for interstitial ectopic pregnancy should be managed with scheduled cesarean delivery at 34-36 weeks of gestation to prevent uterine rupture, which occurs in approximately 30% of cases.

Risk of Uterine Rupture

The risk of uterine rupture following cornual wedge resection is significant and requires careful management:

• A case series found a 30% incidence of subsequent uterine rupture or dehiscence in women who had undergone cornual wedge resection for interstitial pregnancy 1
• This risk is comparable to the uterine rupture rate after classical cesarean deliveries 2
• Uterine rupture can occur as early as the second trimester, even in asymptomatic patients 3

Management Algorithm for Subsequent Pregnancies

Preconception Counseling

• Inform patients about the high risk of uterine rupture (30%) in subsequent pregnancies
• Discuss the need for planned early delivery via cesarean section
• Consider waiting at least 12-18 months after cornual resection before attempting pregnancy to allow for optimal healing

Antenatal Surveillance

1. First Trimester

   • Early ultrasound confirmation of intrauterine pregnancy location
   • Assessment of the cornual resection site for adequate healing
   • Rule out recurrent interstitial pregnancy

2. Second Trimester

   • Detailed ultrasound evaluation of the uterine wall thickness at the surgical site
   • MRI may be considered to better evaluate scar integrity
   • Begin surveillance for early signs of uterine dehiscence even in asymptomatic patients 3

3. Third Trimester

   • Increased frequency of ultrasound monitoring (every 2-4 weeks)
   • Serial assessment of the cornual resection site
   • Limited physical activity and pelvic rest as pregnancy advances

Delivery Planning

• Timing: Schedule cesarean delivery at 34-36 weeks of gestation after antenatal corticosteroids if not delivered earlier 2, 3
• Method: Cesarean delivery is strongly recommended due to high risk of uterine rupture
• Preparation: Ensure blood products are available and surgery is performed at a facility with capabilities for emergency hysterectomy if needed

Special Considerations

Asymptomatic Uterine Rupture

• Asymptomatic uterine rupture has been reported as early as 22 weeks gestation 3
• Regular ultrasound monitoring is essential even in asymptomatic patients
• Any thinning of the myometrium at the surgical site should prompt consideration of earlier delivery

Surgical Approach Considerations

• The surgical technique used for the original cornual resection may impact future pregnancy risks
• Laparoscopic cornuotomy (removal of ectopic pregnancy with preservation of uterine architecture) may potentially decrease the risk for future uterine rupture compared to traditional cornual wedge resection 1, 4

Pitfalls to Avoid

• Allowing vaginal delivery after cornual resection (contraindicated due to high rupture risk)
• Delaying cesarean delivery beyond 36 weeks
• Failing to recognize early signs of uterine dehiscence on imaging
• Inadequate preconception counseling about risks in subsequent pregnancies

By following this management approach, the risks of maternal morbidity and mortality from uterine rupture can be significantly reduced while optimizing outcomes for both mother and baby.